Romney leads, Santorum surges in new Iowa poll

Mitt Romney has claimed a narrow lead over Ron Paul in Iowa, according to a new CNN/Time poll. But it is Rick Santorum who may be showing the most momentum with just days left before the caucuses.

Much of the movement is driven by a collapse in support for Newt Gingrich. He led the previous CNN survey in Iowa with 33% support, well ahead of Romney at 20% and Paul at 17%.

The new results put Romney ahead of Paul 25% to 22%, with Santorum now at 16% -- a jump from just 5% earlier this month. Gingrich has slid 19 points to 14%, though he still leads Rick Perry (11%) and Michele Bachmann (9%).

Santorum has watched all year as a rotating cast of Republicans enjoyed nominal front-runner status, and the media attention that comes with it. His moment may be coming at the most opportune time.

The former Pennsylvania senator may be catching fire with the social conservative voters who also propelled Mike Huckabee to a surprise victory four years ago. Santorum has been lining up endorsements from prominent evangelical leaders, most notably former gubernatorial candidate and Huckabee backer Bob Vander Plaats.

According to the CNN/Time poll, 43% of likely caucusgoers say they can still change their mind.

Things are much less fluid in New Hampshire, where Romney remains the heavy favorite. He now leads the field at 44%, followed by Paul at 17%, Gingrich at 16% and Jon Huntsman at 9%.

Those numbers will probably shift some in the week between Iowa's Jan. 3 caucuses and the Jan. 10 primary, particularly if, as expected, several of the current candidates drop out.

The CNN/Time Iowa poll of 452 likely caucusgoers was conducted from Dec. 21 to 27, with a break in polling on Christmas Day. It has a margin of error of 4.5%.

The New Hampshire poll surveyed 543 likely GOP primary voters in the same period, and has a 4% margin of error.